Charles H. Spurgeon on Psalms 55:13

But it was thou. He sees him. The poetic fury is upon him, he sees the traitor as though he stood before him in flesh and blood. He singles him out, he points his finger at him, he challenges him to his face. But thou. Et tu, Brute. And thou, Ahithophel, art thou here? Judas, betrayest thou the Son of Man? A man mine equal. Treated by me as one of my own rank, never looked upon as an inferior, but as a trusted friend. My guide, a counsellor so sage that I trusted thine advice and found it prudent to do so. And mine acquaintance, with whom I was on most intimate terms, who knew me even as I knew him by mutual disclosures of heart. No stranger occasionally conversed with, but a near and dear friend admitted to my secret fellowship. It was fiendish treason for such a one to prove false hearted. There was no excuse for such villainy. Judas stood very much in this relation to our Lord, he was treated as an equal, trusted as treasurer, and in that capacity often consulted with. He knew the place where the Master was wont to spend his solitude; in fact, he knew all the Master's movements, and yet he betrayed him to his remorseless adversaries. How justly might the Lord have pointed at him and said, But thou; but his gentler spirit warned the son of perdition in the mildest manner, and had not Iscariot been tenfold a child of hell he would have relinquished his detestable purpose.